Electric longboard uses DIY hub motors

As a student of MIT, [Jed Storey] has access to a ton of machine tools, so he decided to build an electric longboard with hub motors by hand. He wound up re-doing a lot of his project, so we can commiserate with him on the trials of R&D.

Inspired by the BWD scooter, [Jed]‘s longboard uses hub motors – the wheel is the motor. The rotors were fabricated in-house, and off-the-shelf stators were wound by [Jed] by hand. There’s a lot of work that went into this build, and the build log is really fascinating in this regard.

The board is controlled by a pistol-grip R/C controller that had been modified to include a dev board and an XBee. For power, an aluminum enclosure was fabricated, strapped underneath the deck, and filled with LiPo batteries. While the build is mostly done, [Jeb] is thinking about scrapping it and moving onto version 2, the HeavyBoard. Check out the video of the board in action.

12 thoughts on “Electric longboard uses DIY hub motors”

That will be no issue at all. Calculations from back EMF show a top speed of 30mph. After mechanical losses hes still getting 15-20 mph, which is still tons faster than I would like to go on a hands free EV ;)

The turning radius is not affected by the fact that it is 4WD. The controllers use current control, so the motors automatically adjust their RPM in turns (outside wheels spin faster, inside wheels slower). It’s sorta like an electronic differential.

The reason the turning radius sucks is because I used over an inch of soft rubber riser pads that don’t transfer the leaning torque into rotating the trucks…plus they are ancient MBS trucks, and are in pretty poor shape (they were what I had on hand when I was designing it).